A fixture 1 shown in FIG. 1 and FIG. 2 has heretofore been used to fix a vehicle component such as a spoiler, which is a plastic molding, to a support member to be electrically connected to a vehicle. FIG. 1 is a sectional view of the fixture 1. FIG. 2 is a sectional view showing how a vehicle component 3 is fixed, by the use of the fixture 1, to a support member 4 secured to the vehicle.
This fixture 1 includes a bolt 12, a bracket 14, a washer 16, and a cushion member 18.
The bolt 12 is a metallic fastening member, and comprises a flat disk-shaped head 12a, an intermediate portion 12b having, for example, a columnar shape coupled to the head 12a, and a threaded portion 12c coupled to the intermediate portion 12b. An external thread is formed on the outer periphery of the threaded portion 12c. The intermediate portion 12b is formed to be larger in diameter than the threaded portion 12c, and a step 13 is formed therebetween.
The bracket 14 is a metallic plate material to hold and secure the vehicle component 3 between the bracket 14 and the metallic support member 4 to be electrically connected to a vehicle body. A through-hole 15 is formed in the bracket 14, and the intermediate portion 12b of the bolt 12 is inserted into this through-hole. The head 12a of the bolt 12 is engaged with the peripheral edge of the through-hole 15 of the bracket 14. In this condition, the head 12a of the bolt 12 is welded to the bracket 14, and the bolt 12 is thereby secured to the bracket 14.
The washer 16 is an annular metallic plate material. The washer 16 is provided to prevent the loosening of a nut 5 threaded and thus tightened to the threaded portion 12c of the bolt 12. The washer 16 contacts the step 13 of the bolt 12 when the bolt 12 is tightened, and is thereby electrically connected to the bolt 12 and the bracket 14.
The cushion member 18 is a flexible plate-shaped or sheet-shaped member made of, for example, a sponge or rubber. The cushion member 18 is provided, for example, to prevent the washer 16 from coming off the threaded portion 12c of the bolt 12.
The fixture 1 configured as described above is used to fix the vehicle component 3 to the support member 4 of the vehicle in the following procedure.
First, the threaded portion 12c of the bolt 12 secured integrally with the bracket 14 is inserted into a through-hole 3a formed in the vehicle component 3.
The washer 16 and the cushion member 18 are then sequentially inserted into the threaded portion 12c of the bolt 12 projecting from the vehicle component 3 on the side opposite to the bracket 14. In consequence, as shown in FIG. 1, the fixture 1 is mounted to the vehicle component 3.
The vehicle component 3 to which the fixture 1 is mounted is then lifted to insert the threaded portion 12c of the bolt 12 into a fixture hole 4a of the support member 4 of the vehicle, and the threaded portion 12c projecting from the support member 4 on the side opposite to the fixture 1 is then tightened into the nut 5. As a result, the vehicle component 3 is fastened and secured to the support member 4 of the vehicle by the fixture 1.
When the vehicle component 3 is attached in this way, the flexible cushion member 18 is formed into a thin sheet shape compressed by being held between the support member 4, the washer 16, and the vehicle component 3. The cushion member 18 thus compressed functions, together with the washer 16, to prevent loosening of the nut 5. That is, the resilient restoration force of the compressed cushion member 18 is used as tensile force for the threaded portion 12c of the bolt 12. The nut 5 is thereby pressed against the support member 4, and loosening of the nut 5 is thus prevented.
The fixture 1 may be used as a ground portion to earth the vehicle body. In this case, the metallic support member 4 to be electrically connected to a vehicle body comes into metallic contact with and is secured with the bolt 12, the bracket 14, the washer 16, and the nut 5, whereby they are electrically connected to each other. Accordingly, the vehicle body is earth-connected via the fixture 1 and the metallic support member 4, with the result that this earth-connection inhibits the deterioration of radio receiving sensitivity and the generation of radio noise that are caused by performance deterioration of an in-vehicle radio antenna.
No prior-art literature related to such a fixture has been discovered through investigation conducted by the applicant.
In the fixture 1 described above, the effect of preventing loosening of the nut 5 deteriorates when the resilient restoration force of the cushion member 18 is reduced by aged deterioration. Accordingly, the nut may loosen and come off.
If the nut 5 loosens, the bolt 12, the bracket 14, the washer 16, and the nut 5 cannot be kept stably in metallic contact in the fixture 1, and the earth performance of the vehicle body may deteriorate. This can cause problems of radio receiving sensitivity deterioration and radio noise generation.
Moreover, when the fixture 1 is used to attach the vehicle component 3 as described above, an assembly operator has to pass the threaded portion 12c of the bolt 12 through the vehicle component 3 and then insert the washer 16. This causes such problems as the washer 16 being dropped.